If any would-be discoverer of ancient monuments is envious of the laurels of Mr. Layard and other celebrities of the same class, let him at once set out by the overland route, and make his way as fast as he can to Ancor-Viat. Few people have yet heard of it, but if what is said of it be true, it must be simply the most stupendous collection of magnificent monuments in the world. If the traveller in Central America, who, like Mr. Stephens, quits the beaten tracks and plunges into the depths of vast forests, is amazed at the ruins of Copan, Palenque, Uxmal, and Chichen, with their huge truncated pyramids, palaces, corridors, and sculptured bas-reliefs, he would, it seems, be still more surprised if he extended his researches to the Empire of Annam, and, advancing toward the utmost boundary of Cambodia, where it skirts Thibet, he came, mounted on an elephant, to the gigantic temples and forests of marble pillars which mark the site of which we speak. It was thus that a French officer in the service of the King of Siam recently visited the spot; and the account he has given of it may be found in the Revue de l'Architecture, and is in great part reproduced in the Revue Contemporaine of December, 1866. No European writer before him has ever mentioned it, and in reading his letters we must make allowances for possible exaggeration. He is a mandarin of the third class, and has obtained the rank of general in command of the Siamese army. M. Perrin (for such is his name) proposes revisiting Ancor-Viat with a complete photographic apparatus; and when he has done this, and had given us the pleasure of examining his photographs, we shall be better able to judge of his veracity. Meanwhile the editor of the Revue Contemporaine is of opinion that the clearness and simplicity of his account leaves little room for doubting its truth.